The invention relates to a heat exchanger for an electronic cabinet, with a folded surface profile in which, alternatingly on both faces, every other fold is closed gastight by a cross cover.
Existing air/air heat exchangers are disclosed in German patent applications DE-AS No. 20 06 759 and DE-AS No. 22 31 469, German patent DE-PS No. 24 44 864 and published German patent application DE-OS No. 30 26 196. These heat exchangers, which may be made of aluminum or plastic, have a multiplicity of parallel folds. The face of each fold is provided with a cross over, and the cross covers of adjacent folds are disposed alternatingly on the one or the other face. Attached to the side surfaces of the folded surface profile are plates, by means of which the folds are covered to form closed flow channels. In the area of cross covers openings for the folds, which open towards the respective side surface, are provided in these plates. In this manner two separate flow paths are obtained for the cabinet air and for the outside air, in which the flow in the folded surface profile goes in opposite directions. These heat exchangers replace a part of the housing wall of the electronics cabinet, or they may be inserted in the electronics cabinet door. They serve to dissipate the heat generated by the electronic components in the electronics cabinet, while the interior of the electronics cabinet remains closed and therefore dustproof. Producing the folded surface profile with its cross covers is expensive. In German patent DE-PS No. 24 44 864, for example, an embodiment of the folded surface profile is described where sheet metal strips with folded faces are joined to each other and bonded to the two cover plates. The folds bonded to each other form the cross covers, and the folded profile itself is formed by the two cover plates. To assure dustproofing, the bond between the folds as well as between the sheet metal strips and the cover plates themselves must be made with great care. Moreover, a protracted period of time is required for the adhesive to harden. In the embodiment described in published German patent application DE-OS No. 30 26 196, the folded profile is formed from sheet metal bent into a meander shape or plastic molded into a meander shape. To provide cross covers, sheet metal parts or appropriately shaped plastic parts must be attached singly to the face and possibly also bonded to the folds. Both production methods are extremely expensive because of the personnel and time required, even in mass production.